1. Field of the Invention
The present invention relates generally to two-dimensional templates and, more particularly, to a two-dimensional design template used for designing, evaluating and measuring human occupant accommodation and seating in a seated environment.
2. Description of the Related Art for Automotive Vehicle Seats
Automotive vehicle seats have three primary functions: (1) position occupant for the driving task; (2) support comfortable healthy sitting postures; and (3) protect occupant upon vehicle impact. A deformable pad on a mechanically adjustable seat frame accomplishes the first function and the second function is accomplished through the geometrical and mechanical properties of the deformable pad composed of padding, suspension and upholstery. The third function is accomplished by seat and restraint systems to restrain the occupant during a vehicle impact. The first two functions determine the greatest portion of the occupant's perceived level of comfort. Position has been considered a primary determinant of occupant comfort and posture has been relegated to the occupant's ability to adapt to the vehicle environment. A major function of seat position and its supporting surfaces is, however, to support the occupant's posture. Thus, there is a need in the art to provide a design tool for automotive vehicle seats.
It is known in the automotive manufacturing industry that seat design relies on a tool built in the early 1960's to represent the position of the hip joint (SE H-point) and leg links for locating the position of the vehicle occupant in the occupant compartment of an automotive vehicle. This tool is known as “Oscar”. Oscar is not constructed for seat design but has become an industry standard because there is no suitable tool that identifies the location of the occupant's torso in the seat. As stated in Volume IV, 1984, SE Handbook as follows:
“The devices described in this standard are intended for applications concerning seated driver side or center occupant accommodation spaces only and are not to be construed as instruments which measure or indicate occupant capabilities or comfort.” (p. 24-27).
One disadvantage of the above tool is that the point of greatest deflection in the deformable pad or seat cushion is defined on the thigh segment which means that the location of this point is dependent upon thigh angle. The greatest deflection in the seat cushion, however, is under the pelvis and is defined by the position and posture of the torso. Another disadvantage with the above tool for use as a seat design tool is the posture of the torso in the above tool is undefined. Since the above tool was built from measurements of men sitting in a bench seat, it is reasonable to assume that the posture is slouched. Current seats are built with the intent of supporting a healthy erect posture in the back. The above tool does not provide any information regarding the location of the anatomical structures that define this posture. Yet another disadvantage of the above tool is that the contour of the interface between occupant and seat does not have contours that represent the deformed centerline contour of the occupant/seat interface.